Pain in the athlete's shoulder is likely to have a mechanical origin, because the athlete performs repetitive high-stress activity. Proper treatment is based on understanding the biomechanics and physiology of the tissues, as well as the demands of the patient's specific athletic activity. Correct rehabilitation is the key to successful conservative and surgical management. A return to previous activity depends on restoring the normal biomechanics, either through conservative management or surgery. Some of these problems are unsolved and remain fruitful areas for future research.